High School Biology: Cell Reference

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Objective for This Multi-Week Lab.

      At the conclusion of this multi-week lab, you will understand how to
"do" ecology.

Equipment Needed for Your Ecological Research Study.

      The equipment you will need will depend entirely on the research
question and project you have chosen to persue.  You may sign out any
research equipment I have in the ecology lab on a day to day basis.  If I
cannot equip you with the ideal piece of equipment to collect a particularly
hard to collect data set for your project, I encourage you to use your
imagination and either make the equipment yourself or re-evaluate why you
needed to collect such logistically difficult data to begin with.  Be
creative, yet note that reality is often constraining.

What Your Group Should Hand In At the End of Class Today.

      Before leaving the lab today, you should hand in a one page research
proposal which should include:

      - the names and phone numbers of the people in your group, 
      - the title of your project, 
      - your research question in one sentence, 
      - your hypothesis(es) about the answer(s) to that question,  
      - a brief description of the methods you will use, 
      - list of equipment you will need and where you can get them,
      - and a time table outlining when your group can get together to
        conduct your study.

      Note that you will also need to make at least one copy of the above
research proposal to take with you.  Do not leave until you have consulted


page 2 II.  Specific Suggestions for the Abstract (length = 200-250 words). 
     1)  This section contains a short summary of every section in your
report.  Cover the main points only.
      2)  In reality, the abstract will be the only part of your paper that
will be read by the majority of those who get past the title; therefore,
tailor the prose for maximum speed, simplicity and impact.

III.  Specific Suggestions for the Introduction (length = 1 page).       
     1) Introduce the general topic of the report.  Why is it of interest?
     2)  State the specific question that is the subject of the report.     
     3)  State an hypothesis that may offer an answer to your question and
explain briefly how your hypothesis answers your question.       
     4)  There may be alternate hypotheses that may answer the same question.

If so, they should be mentioned and your studies must be designed to
distinguish among competing hypotheses.
      5)  If there are other questions that your report addresses, then
repeat steps (2) - (4) for each one.

IV.  Specific Suggestions for the Materials and Methods (length = 1 page)   
     1)  This section describes the procedure you used to address the
question from the Introduction.
      2)  Include all of the necessary and sufficient detail for the reader
to be able to duplicate your studies exactly.  Distinguish between essential
detail and extraneous detail (e. g., studies were carried out on Earth by
Homo sapiens) and omit the latter.
     3)  Replicate your measurements as many times as possible. 
     4)  For every experimental design there are important implicit
assumptions.  Be sure to address the critical ones.
      5)  Comment on the accuracy of your measurement techniques, when
relevant.  E.g., to how many significant digits did you measure such and such
(e.g. q 0.001 gm or q 5 mm)?
      6)  How confident you are depends on the amount of "experimental error"
you have been unable to avoid.  There are two sources of error (not including
mistakes!).  One source is measurement error, which corresponds to the
resolution of your equipment (e.g. did you measure distance with a tape
measure or with a micrometer).  The second source of error is due to
"inherent variation" in whatever it is that you are measuring.  For example,
if you were measuring the diameters of 10 different trees that were all 5 yrs
old, you would expect some difference among them.  It is always good to
design your experiments so that measurement error is much less than the
inherent variation in the quantity measured.
      7)  The best way to estimate "experimental error," due to any sources,
is to replicate a given treatment more than twice.  If the number of
replicates is less than say 8, then error may be estimated by the equation: 
error = q (Max. - Min. values)/2.  If you have more measurements, say "n," of
the variable "x," for which the average is "Ave," then estimate the standard
deviation using:
           (  x12 + x22+ ... + xn2 - n * Ave2   )
           (               n - 1                )                           

      8)  There are specific means by which experimental error, statistical
confidence, and hypotheses testing are to be worked into the design of your
project, depending on your particular question.  You must seek the advice of
your instructor about the statistical analyses you need prior to collecting
any data.
         page 3                                                             
         V.  Specific Suggestions for the Results (length = 1 page).       
      1)  This section contains all of the results of the
experiments and other measurements you made.  
      2)  Any statistical tests are reported in your Results; however,  this
section contains NO interpretations of your results.
      3)  Only use the word "significance" when discussing a statistical
test.  Do not say "our results were significant" in any other context. 
      4)  For every data set there exists an optimum format for presentation.

This format may be a combination of tables and figures (e.g. scatterplots,
bar graphs, etc.) that are
              a)  well documented and easy to read
              b)  illustrate the data with a minimum of redundancy    
              c)  enable the reader to quickly perceive the results
       5)  Poorly conceived graphs will obscure the data and leave the
readers unconvinced of your results.

VI.  Specific Suggestions for the Discussion (length = 1 page).   
      1)  This section contains your interpretation of your results.  Do your
data support your hypothesis(es)?  How "confident" are you in your statements
(see below)?
is accept or reject hypotheses with a finite, numerical degree of
"confidence" (e.g. 95% or 99%).  No scientist can ever be 100% sure.       
     3)  Explain to the reader what the graphs and figures say.  Avoid
recitation of detail previously presented, but cite table and figures by
number as evidence of your statements.
      4)  Never over extend yourself beyond your database.  Abstain from
speculations that your data do not specifically support.  Feel free to
suggest new hypotheses for future work, but do not present new data.
      5)  Be conservative in your assessments, but do not make excuses.

II.  Specific Suggestions for the Literature Cited.
      1)  Note that you will only need this section if you cite other
previously published material somewhere in your paper, (e.g. if you used
previously published methods).  
      2)  Each citation should have:  Author(s).  Year.  Title of paper. 
Journal.  Volume: Pages.   

print on letter head

                              GUIDELINES FOR POSTERS 

                              TO BE PRESENTED IN CLASS 


      The guidelines for posters are similar as those for your manuscript,
except that posters should be designed for brevity of text and clear visual
impact.   Curiously, there are no decent texts on how to design research
posters so you will be very much left to your own creative artistic
abilities.  What follows is a format for the scientific poster for this

I.  General Suggestions.

      1)  Your poster should contain 8 panels: TITLE panel
(containing your Title, names, date, and your Abstract verbatim from your
manuscript), Introduction panel, Materials and Methods, Results, Discussion,
Conclusions (in list form), Acknowledgements (e.g., project from BIOL 301)
and Literature Cited (if any).  Each section serves a specific function
detailed below.
      2) These panels should be organized from upper left to lower right in
order of presentation.
      3) Type or word-process every word using VERY LARGE BOLD PRINT, double
space, with at least 1" margins along all edges of all panels.
      4) Use the handout for manuscripts and write your paper first.  Then,
whittle all of the text down to the barest of short sentences and phrases for
each panel of your poster.  Remember you will be presenting your research
study orally directly from each panel of your poster.